Process for reacting sultones with cellulosic materials to produce cellulosic materials having both basic and acidic groups and product produced

ABSTRACT

Cellulosic material is reacted with either 2chloroethyldiethylamine hydrochloride or 2-aminoethylsulfuric acid so that either diethylaminoethyl cellulose or aminized cellulose is formed. These materials are then reacted with a hydrocarbon sultone such as propane sultone in a suitable solvent without catalyst to add the sultone at the nitrogen group. The resultant products have both acidic and basic groups in the same molecule and are zwitterion-exchange celluloses.

Unite States ateri t 11 1 ard et al.

[451 Dec. 17, 1974 PROCESS FOR REACTING SULTONES WITH CELLULOSIC MATERIALS TO PRODUCE CELLULOSIC MATERIALS HAVING BOTH BASIC AND ACIDIC GROUPS AND PRODUCT PRODUCED [75] Inventors: Truman W. Ward; Ruth R.

Benerito, both of New Orleans;

Ralph J. Berni; Donald M. Soignet, both of Metairie, all of La.

[73] Assignee: The United States of America as represented by the Secretary of Agriculture, Washington, DC.

Filed: Nov. 15, '1972 App]. No.: 306,771

[52] US. Cl. 8/116 R, 8/181 [51] Int. Cl D06m 1/00 [58] Field of Search 8/1 16 R, 181

[56] References Cited UNITED STATES PATENTS 3,506,390 4/1970 Naps 8/116 R 3,698,857 10/1972 Vigo et al. 8/116 R Primary Examiner-Stephen J. Lechert, Jr.

[57] ABSTRACT 6 Claims, No Drawings PROCESS FOR REACTING SULTONES WITH CELLULOSIC MATERIALS TO PRODUCE CELLULOSIC MATERIALS HAVING BOTH BASIC AND ACIDIC GROUPS AND PRODUCT PRODUCED A non-exclusive, irrevocable,, royalty-free license in the invention herein described throughout the world for all purposes of the United States Government, with the power to grant sublicenses for such purposes, is hereby granted to the Government of the United States of America.

This invention relates to chemical modification of cellulosic derivatives. More specifically, this invention relates to the modification of diethylaminoethyl cellulose and aminized cellulose with propane sultone to yield zwitterion cellulosic derivatives which have excellent ion exchange properties. The products thus produced lend themselves to further reaction with either acid reactive or basic reactive substances.

An equation which would represent the pertinent reaction of this invention is this:

cess for reacting cellulosic textiles having amino groups.

with propane sultone to produce fibrous cellulosic derivatives having zwitterion exchange properties. Textiles thus prepared would have both acid and basic groups in the same molecule.

U.S. Pat. No. 3,506,390 discloses a process wherein aqueous sodium hydroxide has been used to produce alkali cotton which was reacted in aqueous solutions of propane sultone to produce a material containing acid sites but no basic sites and the process requires the by droxide to be in the bath in order to effect reaction.

German Pat. No. 941,977 discloses a process by Helberger et al. wherein certain sultones are reacted with ammonia and amines. No mention is made of reaction of the sultones with amine groups which would have the amine groups attached to cellulose.

We' have now discovered that a cellulosic material with primary amine groups attached (aminized cotton) can be reacted with propane sultone to produce cellulosic materials having both basic and acidic groups. The reaction proceeds readily without need of a catalyst to yield a product with zwitterion exchange properties.

We have further discovered that cellulosic material with the related tertiary amine (DEAE) grouping can likewise be reacted with the said propane sultone. It has further been calculated that butane, pentane, and higher sultones should react in the same or similar manner.

By the process of the present invention cellulose is reacted to add an amine group to the cellulose. DEAE- cellulose can be prepared by any of several processes. An acceptable one would be that one disclosed in U.S. Pat. No. 1,777,970. Aminized cotton can best be prepared by the method described in Guthrie, et a]. which appears in Textile Research J. 17, pp. 625-629 (1947), with the title Introduction of Amino Groups into Cotton Fabric by the Use of 2-Aminoethylsulfuric Acid. The cellulose with the amine or DEAE group attached, for purposes of this invention, is then reacted with a hydrocarbon sultone such as the preferred sultone in solu-. tion in the proper solvent.

The preferred solvent for reacting DEAE-cellulose with the sultone is either tertiary butanol or methanol while for aminized cellulose a primary alcohol such as methanol is required. The reaction is carried out while the cellulosic material is wet with the propane sultone solution. Temperatures can be varied from 25 to C,

and the length of time can be varied from 1 to 24 hours.

or linen. Means of brining cellulosic material into contact with the sultone solution include immersion, dipping, padding, and spraying. Although .the sultone employed throughout the investigative efforts which led to the present invention was propane sultone, it should be obvious to those skilled in the art that other sultones, such as butane sultone, can be employed in the same manner. The concentration of the sultone in the solution can be variedover a wide range although the range of 5 to 20 percent will usually suffice.

In a typical laboratory demonstration of this process a dry DEAE-cotton fabric of 0.61 meq. N per gram was immersed in a'solution of 10 percent propane sultone in tertiary butanol and the immersed sample held at a temperature of 50C for 20 hours. The sample was removed from the reactant solution and thoroughly washed with water and dried. The sample was analyzed,

yielding 0.26 meq. of sulfur per gram of product. An aminized cotton of 0.55 meq. of N per gram of fabric treated the same way except for the substitution of ,methanol for the tertiary butanol yielded 0.39 meq. of

sulfur per gram of product.

To summarize, the present invention can best be described as (l) fibrous sultone-amine celluloses and (2) the process for producing the fibrous sultone-amine celluloses and for imparting zwitterion-exchange properties to cotton and other cellulosic materials, the process comprising reacting the cellulosic material with a compound selected from the group consisting of 2-chloroethyldiethylamine hydrochloride and 2-aminoethylsulfuric acid to form respectively the diethylaminoethyl cellulose or the aminized cellulose,' which are reacted with a hydrocarbon sultone without benefit of catalyst, thereby adding the sultone to the nitrogen group.

Example l Diethylaminoethylated cotton (DEAE-cotton) was prepared from X 80 weave cotton printclothwhich had been desized and bleached by padding twice with 20 percent beta-chloroethyldiethylamine hydrochloride, drying at 60C for minutes, immersing in 8 percent aqueous sodium hydroxide at 95C for 10 minutes, washing free of NaOH in dilute acetic acid, washing in tap water (pl-1 9) to remove the acetic acid and drying. The fabric had 0.61 meq. N/g. of fabric.

Aminized cotton was prepared from 80 X 80 weave cotton printcloth which had been desized and bleached by padding with a freshly prepared solution containing 20 percent of Z-aminoethylsulfuric acid and 30% NaOl-l, and curing in an oven at 120C for minutes, washing in dilute acetic acid, washing in tap water and drying. The fabric had 0.55 meq./N per gram of fabric.

Comparing DEAE and aminized cottons in methanol and tertiary butanol:

The dry DEAE cotton, aminized cotton and unmodified cotton fabrics were placed in separate cylinders containing 10 percent propane solution in either tertiary butanol or absolute methanol. The containers and contents were all held at 50C for hours before removal of the fabric samples. The fabric samples were washed thoroughly with distilled water and dried the results were as follows:

t-butanol Methanol Fabric Meq.N/g. Meq.S/meq.N Meq.S/meq.N Aminized 0.55 0.07 0.70 DEAE 0.61 0.4 0.50 Unmodified 0 '0 0 EXAM PLE 2 To show that an external amine will not cause reaction with unmodified cotton:

Reactions of unmodified cotton fabric samples were- Sulfur Fabric T-butanol Methanol Unmodified cotton. Ethylamine 0.00 0.02 Unmodified cotton, Triethylamine 0.05 0.00

EXAMPLE 3 To show that another alcohol such as ethanol may be substituted but a different type solvent such as DMF does not work:

Aminized cotton fabric swatches were immersed in.

solution of 10 percent propane sultone in either methanol, ethanol, or DMF and held at a temperature of 50C for 20 hours. The fabric samples were removed from the solution, wahsed thoroughly in distilled water and dried.

Methanol Ethanol DMF %Su.lfur 1.26 1.16 0.10

EXAMPLE 4 This examples showsthat the amount of reaction with the propane sultone varies with the amount of nitrogen present. 4

DEAE cottons with different nitrogen contents were reacted with a 10 percent solution of propane sultone in tertiary butanol at 50C for 20 hours. The samples were removed from the solution and washed with water and dried before analysis.

% Nitrogen Sulfur" EXAMPLE 5 This example shows that the concentration of propane sultone in solvent can be varied but that concentrated solutions are neither desirable nor necessary.

Conditions as in Example 4 except only DEAE cotton of 1.0 percent nitrogen was used and concentrations of propane sultone varied. The results were as follows:

.% Propane Sultone Sulfur in Product EXAMPLE 6 1 hr. 3 hrs. 6 hrs. 16 hr. 24 hr. 32 hr.

% sulfur 1.85 1.90 2.0 2.25 2.35 2.45

EXAMPLE 7 Example 6 except substitute aminized cotton fabric in methanol for DEAE cotton fabric in tertiary butanol. Results were as follows:

1 H1". 3 6 Hrs. 20 Hrs.

% sulfur 0.78 I 0.83 0.95 1.26

EXAMPLE 8 This example will illustrate the effect of temperature on the reaction of the propane sultone with DEAE cotton.

Example 6 except use 1 hour and .vary temperature. Results were as follows:

25C 35C 40C 50C 60C 75C sulfur 1.35 1.60 1.65 L85 2.00 2.25

EXAMPLE 9 Meq. N/g. MegS/mgN Bio-Rad DEAE Powder Our DEAE Fabric l. A process for imparting Zwitterion-exchange properties to diethylaminoethyl cellulose, the process comprising contacting said diethylaminoethyl cellulose with an organic solvent solution of about from 5 to 20 percent hydrocarbon sultone at 25 C. to 75 C. for about 1 to 24 hours.

2. A process for imparting Zwitterion-exchange properties to aminized cellulose, the process comprising contacting said aminized cellulose with a primary alcohol solvent solution of about from 5 to 20 percent hydrocarbon sultone at 25 C. to 75 C. for about 1 to 24 hours, using the longer periods of time with the lower temperatures.

3. The process of claim 1 wherein the hydrocarbon sultone is propane sultone.

4. The process of claim 2 wherein the hydrocarbon sultone is propane sultone.

5. The product produced by the process of claim 3 wherein the nitrogen content is as high as about 2 percent and the-sulfur content is as high as about 3.5 percent with respect to the weight of the sultone-cellulose.

6. The product produced by the process of claim 4 wherein the nitrogen content is as high as about 1.0

percentand the sulfur content is as high as about 1.5

percent with respect to-the weight of the sultonecellulose. 

1. A PROCESS FOR IMPARTING ZWITTERION-EXCHANGE PROPERTIES TO DIETHYLAMINOETHYL CELLULOSE, THE PROCESS COMPRISING CONTACTING SAID DIETHYLAMINOETHYL CELLULOSE WITH AN ORGANIC SOLVENT SOLUTION OF ABOUT FROM 5 TO 20 PERCENT HYDROCARBON SULTONE AT 25*C. TO 75*C. FOR ABOUT 1 TO 24 HOURS.
 2. A process for imparting Zwitterion-exchange properties to aminized cellulose, the process comprising contacting said aminized cellulose with a primary alcohol solvent solution of about from 5 to 20 percent hydrocarbon sultone at 25* C. to 75* C. for about 1 to 24 hours, using the longer periods of time with the lower temperatures.
 3. The process of claim 1 wherein the hydrocarbon sultone is propane sultone.
 4. The process of claim 2 wherein the hydrocarbon sultone is propane sultone.
 5. The product produced by the process of claim 3 wherein the nitrogen content is as high as about 2 percent and the sulfur content is as high as about 3.5 percent with respect to the weight of the sultone-cellulose.
 6. The product produced by the process of claim 4 wherein the nitrogen content is as high as about 1.0 percent and the sulfur content is as high as about 1.5 percent with respect to the weight of the sultone-cellulose. 